Safety-stop for elevators.



A. PETIT.

SAFETY STOP FOR ELEVATOHS., APPLICATION FILED MAR. 27, I9I5.

1,158,150., PaIenIed 001. 26, 1915.

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CULUMBIA PMNDGRAPH C0. WABHINQTDN. D. C.

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ALBERT PETIT. 0E Los ANGELES, CALIFORNIA.

, SAFETY-STOF FOR ELEVA'IORS.

To all whom t may concern.'

Be it known that I, ALBERT PETIT, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles, State ofV California, have invented new and useful Improvements in Safety-Stops for `Elevators, of which the following is a specifica# tion.

This invention relates to safety stops for elevators and the like; and the object of this invention is the provision of simple, efficient and trustworthy means for eliectively stoppingan elevator when itsv speed has 1ncreased toa dangerous point.

The mechanical features may be best understood by reference to the accompanying drawings, wherein I have shown a specific form of 'my invention, and to the following specification wherein said specific forml is described and the operation and utilities of my invention are set forth.

For the purpose of this specification I illustrate a vpreferred specific form of my invention in the accompanying drawings, in whichn l Figure 1 is a vertical side elevation of an elevator equipped vwith my improved stop mechanism, Fig. 2 isa front elevation of the same, Fig. 3 is a detail section taken as indicated by line 3 3k of Fig. 1, and Fig. 4 is a section taken as indicated by line 4 4 of Fig. 1. y

In the drawings the numeral 10 may designate the body of a car or cage of the ele* vator and 11 the way or ways upon whichl the 'cage is adapted to move. Any suitable means may be used for engaging the cage with the ways, as is illustrated at 12.

My improved stop mechanism includes the combination of a gripping' device and a means for normally holding the gripping device in inoperative position, av means, such as a spring means for throwing the;,grip

ping device to operative position, and a' means which is controlled or actuated by the speed of the cage for releasing the holding means which hold the gripping device out of action. The specific details of a preferred form of this mechanism are explained as follows: I provide a horizontally movable pivot 13 uponthe cage 10, saidpivot 13 being mounted'in a small frame 14 which is pivotally mountedatl to the cage itself. A way gripping bar 16 is mounted on the pivot 13 and this bar has in its outer end a notch 17 adapted to normally loosely en- Specification of Letters Patent.

Patented @et 26, 1915.

' Application led March 27, 1915. Serial No. 17,379. i

gage around the way 11 when the bar 1G is in its normal substantially horizontal posi` tion. There are two of these bars 16, one on each side of the cage,'each engaging one of the oppositeways 11. I utilize vertically sliding bars 18v which carry rollers 19 above and belowV the bar 16, so that vertical movement of the bars 18 will cause movement of the bars 16 around their pivots 13. The two vertical sliding bars 18 are joined to a horizontal cross member 20 'at their lower ends; and springs 21 are adapted to press the cross member.20 and the bars 1S downwardly. The springs 21 are merely used for the purpose Aof quickening the action in pressing the cross member 20 and the bars 18 downwardly; the action of these members would be the same without the springs 21 but not so fastV and sure. The bars and the cross member are normally held from downward movement by the vaction of the spring pressed pawl 25 which enters under a roller I26 mounted inthe cross member 20. This pawl 25 is mounted in a suitable bearing Vor hanger 27, the spring 28 pressing it outwardly into position beneath theroller 26. A hand lever 29connected by rod 30 with a lever 31 which is connected at 32' with the cross member 20, serves the purpose of raising the cross member and the bars 18 to their normal position. The pawl 25 is operated by the horizontal movement, in either direction, of an arm 35, to which arm the pawl is pivotally connected at 35; and the arm `has a cam 37 `on its en d bearing against the hanger 27, the cam being of such shape that when the arm 35 is moved in either horizontal direction the pawl 25 is withdrawn from beneath the roller 26, allowing the cross member to be moved downs wardly.

It will be seen from the foregoing `description that the mechanism so far described includes va means for gripping the way, and a means `for normally holding said gripping means in'its inoperative position, and means (the springs 21) for `throwing the gripping means to operative positions when the holding means is released. The mechanismv for operating theholding means to release it is now explained. On the under side of the cage I mount a shaft 40 in bearings 41 which'are supported on oscillating arms 42; and a spring 43 serves the purpose of throwing the arms 42 in the direction shown; so that a friction wheel 44 which is v`mounted( upon the shaft 40 will be thrown kept at a constant vdistance from each other to keep the gears 46 and 47 in proper mesh. The gearing arrangement is such that the shaft 48 revolves at a considerable speed. Mounted upon this shaftv 48 beneathvthe arm 35 which operatesy the pawl 25, I place a wheel or'disk 55carrying a plurality of outwardly movable weights 56. These weights are opposed in their outward movement by the springs 57; and the springs are of such strength that the weights will not. move outwardly until a certain predetermined speed ie eteeined. When the eee exeeede this pre titttllllllltli Sllti, then Weights itinere thrown outwardly by centrifugal force and they strike the arm.35 and move it in one direction 0r the other, so as to retract the pawl 25v and allow the cross member 20 to be moved downwardly by the springs 21. This movement of the cross member and of the bars 18 connected thereto causes the bars 16 to move to a diagonal position so that the notches 17will grip or kbind on the ways 11; and the car is then held from further downward movement.v Since movement of the arm 35 in either direction will cause retraction of the pawl 25, it will beseen that excessive speedV ofthe car either upwardly or downwardly will cause retraction of the pawl andY operation as described. springs 57 may be arranged in strength so as to allow the outward movement of the weight 56 at any predetermined speed.

Having described a specilic form of my invention, I claim:A

l. In combination with a verticalway and anelevator cage movable thereon, a way gripping means on the cage embodying a The way gripping bar holding a notch adapted to loosely engage around the way when the bar is in substantially horizontal position, a horizontally movable pivot on the cage on which pivot the bar is mounted, means including a pawl for holding the arm nor- Amally in substantially horizontal position,

sprinoP means for throwing the arm to an inclined position, an arm connected with said pawl so that movement of the arm causes movement of the pawl to release the way gripping arm, and means to move said pawl arm including a wheel mounted 0n the cage and in peripheral frictional contact with the way, spring means for holding said wheel in contact with the way, another wheel geared to said first mentioned wheel, outwardly movable weights on said last mentioned wheel, and springs opposing the outward movement of the weights, the weights being thrown outwardly by centrifugal action to strike the pawl arm, substantially as described.

2.111 eememeeee with e veel el Wwf and an elevator cage movable thereon, a way gripping means, means for normally holding said way gripping means out of action, a frame pivotally mounted upon the car, a way engaging wheel mounted upon said frame, a spring exerting pressure upon said frame to press the wheel into peripheral contact with the way, another Wheel mounted upon said pivoted frame in fixed relation to said first mentioned wheel, gearing connection between the two wheels, outwardly movable weights on the second mentioned wheel, springs opposing the outward movement of said weights, and a member connected to said grip holding means and positioned so as to be struck and moved by said outwardly movable weights on said second mentioned wheel.

In witness that I claim the foregoing I have hereunto subscribed my name this 19th day yof March 1915.

ALBERT PETIT. I/Vitnesses:

JAMES T. BAnKnLnw, ELwooD H. BARKELEW.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

' washington, D. e. 

